Next, unplug the tail lamp housings from the vehicle's wiring harness. If the radio display still dims when the brake pedal is pressed, the problem has to be in the vehicle. In particular, look for a buildup of corrosion between two adjacent pins in a connector, especially along the frame or inside the body.
If the problem is gone, plug one housing back in, then see what happens when you press the brake pedal. If the problem comes back when plugging in one of them, that's the one to look at for the problem.
By the way, I found a similar problem on a friend's son's Chevy truck not too long ago. One of the buttons of solder, (the contact) on the base of the bulb, broke off and was stuck between the right front turn signal terminal and the running light terminal right next to it in the socket. We didn't see it rght away because of the grease in the socket. His left signal worked fine but the right signal blinked real fast and caused all the running / tail lights to turn on, and the radio display flickered.
I put in a call to the administrators to contact beef99 on your behalf. I don't know how to reach him either through the forum unless he's online. Hopefully he will have some more ideas.
Friday, March 12th, 2010 AT 3:12 PM